Transistor characteristics

Material required:

  • Rheostat
  • Voltmeter
  • Ammeter
  • Battery
  • One way key
  • Transistor
  • Bread board

Real Lab Procedure:

  • Connections are made as shown in the circuit diagram.

    

  • The rheostat Rh1 is used to vary base voltage (input voltage) VBE and it is read from voltmeter V1. The base current (input current) IB is measured using a microammeter (µA). The collector voltage (output voltage) VCE is varied using the rheostat Rh2 and readings are noted from voltmeter V2. The collector current (output current) IC is measured by the milliammeter (mA).

Input Characteristics

  • The collector voltage VCE is kept constant (eg. 1V) by adjusting the rheostat Rh2.
  • The base voltage VBE is varied from zero by adjusting the rheostat Rh1.
  • The base current IB is noted in each step.
  • A graph is drawn with VBE along X-axis and IB along Y-axis.
  • The experiment is repeated with VCE kept constant say 2V, 3V, 4V etc. and corresponding graphs are plotted. 

                                              

Output characteristics

  • The base current IB is kept constant (eg. 20µA) by adjusting the rheostat Rh1.
  • Now the collector voltage is increased by adjusting the rheostat Rh2.
  • The corresponding collector current IC is noted.
  • A graph is drawn with VCE along X-axis and IC along Y-axis.
  • The experiment is repeated with keeping IB constant, say 40µA, 60µA, 80µA etc and similar graphs are plotted.

                                    

Observations:

Input characteristics

VCE (1V) VBE (V)      
IB (μA)      
VCE (2V)        
VCE (3V)        
VCE (4 V)        

Output characteristics

IB (μA) VCE (V)      
IC (mA)      
IB (μA)        
IB (μA)        
IB (μA)        

Results:

The graphs shows the input and output characteristics of a transistor.
 
 

Cite this Simulator: